44 (108) Society for Experimental Biology and Medicine. 



i 8 (64). "The results of attempts to cultivate trypanosomes 

 from frogs." A preliminary report : JOSEPH LEWIS and HER- 

 BERT U. WILLIAMS. (Presented by AUGUSTUS B. WADS- 

 WORTH.) 



During the year 1904 an effort was made in the pathological 

 laboratory of the University of Buffalo to make studies on hema- 

 tozoa in the lower animals. In a considerable number of normal 

 cats, dogs, rabbits and guinea-pigs no hematozoa were found. The 

 results of other examinations were as follows : 5 1 English sparrows 

 (Passer domesticus), half in the winter, half in the spring, all nega- 

 tive ; 27 mud-puppies {Necturus maculatus) in March, all negative ; 

 40 toads in the summer, all negative. In 140 frogs from the Niagara 

 river there occurred the following infections : 14 with Trypanosoma, 

 5 with Drepanidium, I with Filar ia. Drepanidium was found both 

 in the summer and fall. The infections with Trypanosoma were 

 distributed as follows : 



In July, of 1 5 frogs, 2 showed trypanosomes. 



In August, of 26 frogs, 10 showed trypanosomes. 



In September, of 14 frogs, 2 showed trypanosomes. 



From October to December, of 85 frogs, none showed try- 

 panosomes. 



In one case Trypanosoma and Drepanidium occurred in the 

 same blood. The trypanosomes had the usual characters of Try- 

 panosoma rotatorium (ranarum). They were in no case numerous ; 

 two were rarely seen in one low-power field. The frogs appeared 

 healthy. Eight attempts to inoculate normal frogs by way of the 

 peritoneum with the blood of infected frogs gave negative results. 



Attempts at cultivation. — The blood of frogs and toads was 

 taken to make blood-agar (used by Novy and MacNeal for the 

 cultivation of trypanosomes). 1 The blood was first examined care- 

 fully to see that it was free from parasites. The animal was ether- 

 ized and placed in HgCl 2 solution 1 to 1,000 for 1 5 minutes, rinsed 

 with distilled water, opened with all precautions, the blood from the 

 heart taken with a sterile pipette, and mixed rapidly with the water 

 of condensation on slanted agar tubes (made with meat extract and 

 peptone, and slightly alkaline to litmus). Two or three drops of 

 blood were used for each tube. The tubes were scaled with rub- 



1 See page 23 (87). 



